The present invention relates generally to new and novel hydraulic filtering for a motor vehicle limited slip differential. More particularly, the present invention relates to new and novel hydraulic filtering for a motor vehicle limited slip differential which is particularly suitable for use in a motor vehicle limited slip differential which draws hydraulic medium from an axle sump by a vacuum generated by a hydraulic pump and transports the hydraulic medium to a hydraulic pump intake sump reservoir.
In many motor vehicle limited slip differentials, a pickup tube draws hydraulic medium from an axle sump by a vacuum generated by a hydraulic pump and transports the hydraulic medium to a hydraulic pump sump reservoir. Over time, the hydraulic medium tends to gather particulate contamination from, for example, foreign material which is introduced from outside the motor vehicle limited slip differential, oxidation or metallic particles removed from the internal components in the motor vehicle limited slip differential and foreign material which precipitates as solid material from the hydraulic medium itself. Such particulate contamination can, if not removed from the hydraulic medium, cause excessive wear and/or damage to the internal components of the motor vehicle limited slip differential.
Known prior art hydraulic fluid pickup tubes have generally had a circular or a square cross-sectional configuration, thus allowing all but the largest particulate contamination to pass therethrough. Thus, the remaining particulate contamination can cause excessive wear and/or damage to the internal components of the motor vehicle limited slip differential. In addition, large pieces of particulate contamination, which tend to be substantially spherical in configuration, may block all, or at least a substantial part of the hydraulic medium flow through the hydraulic medium pickup tube if caught or lodged therein. This can result in less than the desired rate of flow of hydraulic medium to the motor vehicle limited slip differential, again resulting in excessive wear and/or damage to the internal components of the motor vehicle limited slip differential.
A preferred embodiment of the present invention is, therefore, directed to a limited slip differential for a motor vehicle having a hydraulic medium plenum and pickup tube assembly which draws hydraulic medium from an axle sump by a vacuum generated by a hydraulic pump and transports the hydraulic medium to a hydraulic pump intake sump reservoir, the hydraulic medium plenum and pickup tube assembly having a cross-sectional configuration which maintains the desired hydraulic medium flow rate, while being "thin" in at least one direction to filter out particulate contamination.
Other advantages and novel features of the present invention will become apparent in the following detailed description of the invention when considered in conjunction with the accompanying drawings.